Woodpecker © 1981 Amenip.
Main CPU : Zilog Z80 (@ 3.072 Mhz)
Sound Chips : Namco 3-channel WSG (@ 96 Khz)
Screen orientation : Vertical
Video resolution : 224 x 288 pixels
Screen refresh : 60.61 Hz
Palette Colors : 16
Players : 2
Control : 4-way joystick
Buttons : 1
Also licensed to Palcom Queen River.
The version that Amenip licensed to Palcom Queen River most likely has different colors & ladders arranged in a different way than the version they sold themselves as is the case with Naughty Mouse.